There are many types of smoke alarms in use today. The conventional smoke alarm used in the home is a relatively small, battery-powered unit which is mounted at locations where fires are likely to occur. For instance, many homeowners mount such alarms in the kitchen; others may mount the alarms at the tops of stairways, in bedrooms, etc.
While smoke alarms have undoubtedly saved many lives, certain problems have been noted. For instance, it has been found that cooking smoke may set off the alarm, as well as smoke generated when a number of smokers gather in a room where an alarm is located. Furthermore, some types of alarms are known to shut off in response to water vapor produced by showering. It is particularly annoying, not to mention inconvenient, for an alarm to be set off in such a manner.